Tanimbar Corella uses “tool” to get at the coconut kernel

Ang Siew Siew documented a Tanimbar Corrella (Cacatua goffini) digging into a coconut in an earlier post. She returned to the Sentosa Waterfront site a few days later and returned with a major ornithological discovery – a tool using corella, with an 8-minute video as evidence. Yes some birds do use tools but as far as can be ascertained, a tool using Tanimbar Corella has not been reported earlier.

Tanimbar Corella with a broken off piece of spiklet to be used as a tool

According to Siew Siew: “…The corella made numerous attempts (9 counts) to get at the flesh of the coconut using old inflorescence spikelets and leaf midribs of the coconut palm (Cocos nucifera) it broke off with its beak (above, below). During my approximately one hour of observation, it took only one 10 minute break with the rest of the time busy at work. It moved from one exposed coconut to another (there were 3 in that bunch) using the same antics. I guess the coconut flesh must be really sweet and tasty such that this corrella found it hard to resist and put in all effort to retrieve it.

Tanimbar Corella with another broken off piece of spikelet to be used as a tool

“The mystery remains as to what animal managed to break the shell of the coconut for the corrella to enjoy the flesh of the fruit. Is it possible that the correllas have done it?

“There were 5 to 6 correllas on Tuesday, 2nd August vying to feast on the exposed fruits but on Friday, 5 August there was only this lone ranger. I wonder why the rest did not return or why this one did not join the rest” concluded Siew Siew.

Ang Siew Siew
Singapore
5th August 2016

Note:
According to Wikipedia, Covids (crows, ravens and rooks) are well known tool users. They make use of twigs, sometimes, metal wires to catch and impale larvae. Finches and woodpeckers similarly insert twigs for the same purpose.

Parrots have also been known to use tools to wedge nuts so that they can crack it open. The South American Hyacinthine Macaws (Anodorhynchus hyacinthinus) can crack the hard shell of the Acrocomia totai palm nut to get at the kernel. But then the fruit is small, about 2.5-5cm diameter LINK.

Cockatoos have powerful bills that they use to gain entry into hard nuts, even to rip branches to get at the insect larvae inside (Rowley, 1997). But the coconut is at least three times larger than the South American palm nut. Can they have chipped through the hard shell of the coconut?

Reference
Rowley, I., 1997. Family Cacatuidae (cockatoos). In: del Hoyo, J., A. Elliott & J. Sargatal (eds.), Handbook of the birds of the world. Vol. 4. Sandgrouse to Cuckoos. Lynx Editions, Barcelona. Pp.246-279.

This post is a cooperative effort between Birds, Insects N Creatures Of Asia and BESG to bring the study of birds and their behavior through photography and videography to a wider audience.

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